Description
The ERM280 is a high-accuracy rotary encoder (position detector) manufactured by Heidenhain and used as a spindle/C-axis feedback encoder in CNC machine tool systems. It provides extremely precise angular position data that a CNC controller or drive uses for C-axis control, spindle orientation, and high-accuracy motion feedback.
👉 In Mitsubishi CNC documentation, ERM280 is listed as a “spindle side accuracy serial output encoder” used as an option for precise C-axis control in spindle drives.
📌 Key Technical Details
📍 Encoder Variants
The ERM280 series comes in multiple line-count / resolution variants, such as:
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ERM280 1200
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ERM280 2048
These differ mainly in resolution (number of scale marks) and maximum rotational speed.
📏 Resolution & Precision
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ERM280 1200:
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Minimum detection resolution: ~0.0000183° (≈ 19,660,800 counts/rev)
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Compatible max speed: ~20,000 rpm
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ERM280 2048:
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Minimum detection resolution: ~0.0000107° (≈ 33,554,432 counts/rev)
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Compatible max speed: ~11,718 rpm
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These extremely fine angular resolutions make the ERM280 suitable for very precise spindle positioning and C-axis control in advanced CNC operations.
🧠 How It Works in Systems
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The ERM280 itself is mounted on the spindle or its gear/mechanism and uses magnetic or optical scanning techniques (depending on exact model) to detect rotational position.
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Its raw signals (often SIN/COS or A/B signals) are typically fed into an interface/conversion unit (e.g., EIB192M/EIB392M). This unit converts them into a high-resolution digital serial output that Mitsubishi drives/controllers can use.
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These converters allow attachment to modern CNC/spindle drives for high-gain servo response and accurate motion feedback.
⚙️ Typical Applications
The ERM280 is used in applications like:
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C-axis machining and orientation
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Synchronous tapping and spindle indexing
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High-precision spindle speed/position feedback for servo control
Because of its high resolution, it is often chosen for advanced CNC machine tools where position accuracy is critical.
📌 Summary
| Feature | Specification |
|---|---|
| Type | High-accuracy rotary encoder (Heidenhain ERM280 series) |
| Purpose | Spindle/C-axis feedback in CNC systems |
| Resolution examples | 19,660,800 p/rev (1200) |
| Max speed | Up to ~20,000 rpm |
| Typical use | C-axis control, spindle orientation, high-accuracy feedback |
| Interface | Via serial conversion units (e.g., EIB192M/C4, EIB392M/C6) |